题干

手中有一叠薄纸,若要测出其中一张纸的质量,下列方法可取的是(  )

A:先称出一块铁的质量,再称出一块铁和一张纸的总质量,然后用总质量减去一块铁的质量

B:取出10张薄纸,称出总质量,然后除以张数10,就得到每张的质量

C:取出较多张数的纸(如100张)称出总质量,然后除以所取纸的张数,就得到一张纸的质量

D:以上方法都可取

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答案(点此获取答案解析)

C

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    Which boy hasn't dreamed of being a cool secret agent (特工)? The wonderful fighting abilities and the world-saving adventures are much more colorful than most people's everyday lives. Well, Cody Banks is just like any other boy, except that he is not just dreaming. He has a big secret his friends never know about. He was trained to be a spy (间谍)by a special CIA programme, which was made to look like a summer camp. He learned high-speed driving, hand-to-hand fighting and the use of high-tech tools.

    After proving he could become a young hero by saving a baby from a runaway car, Banks gets his first real task. He must make friends with a popular girl at school, Natalie Connors. Then, he must spy on her father, a scientist who has developed a dangerous technology (技术).Banks must stop a group of bad people from forcing Natalie's father into using the technology to endanger the world.

    The CIA may have taught him first-class self-defense moves, but they didn't show him how to talk to girls. Banks has zero ability when it comes to dealing with girls. How can he get around his problem and get an invitation to the girl's upcoming birthday party? Will he finally become Natalie's boyfriend and find out whatever he can about her father's work?

    Agent Cody Banks has everything that young people are interested in: big explosions, breath-taking performances and funny girl-dating experiences. It was listed No.2 in the American box office last week.

    “This story is interesting and fun for the whole family to enjoy, and especially cool for young boys,” said Paul Perkins, a film reviewer in the US.